Table 1 Demographic and clinical characteristics of infants ≥ 35 0/7 weeks.

Female sex

29.7

41.7

0.62 (0.40-0.96), 0.03

Caucasians race

59.8

54.9

1.24 (0.81-1.90), 0.33

Gestational age^a

38.8 (1.6)

38.4 (1.7)

0.01

Gestational age <37 weeks

13.7

19.2

0.42 (0.23-0.79),0.008

Birth weight^a

3208 (514)

3175 (558)

0.51

Birth weight <2500 g

8.22

10.2

0.64 (0.28-1.46),0.28

Small for GA status

10.5

8.51

2.10 (0.97-4.56), 0.06

Cesarean delivery

51.6

36.6

1.37 (0.89-2.10), 0.16

Maternal diabetes

19.2

15.7

1.22 (0.69-2.13), 0.49

Maternal chorioamnionitis

21.0

9.79

2.07 (1.13-3.79), 0.02

Maternal steroids

12.3

4.68

5.22 (2.09-13.0), <0.001

Meconium aspiration

20.6

14.9

0.81 (0.46-1.46), 0.49

Apgar score at 1 min^b

8 (5,8)

8 (7,9)

<0.001

Apgar score at 5 min^b

8 (7,9)

9 (8,9)

0.004

Delivery room oxygen

77.6

42.6

2.27 (0.99-5.14), 0.05

Delivery room CPAP

73.9

39.2

2.38 (1.06-5.36), 0.04

Delivery room positive ventilation

22.8

11.1

1.30 (0.70-2.44), 0.41

Delivery room intubation

5.94

3.83

1.19 (0.37-3.85), 0.77

Surfactant therapy

7.31

3.83

1.37 (0.51-3.66), 0.53

Average highest FiO₂^a

0.46 (.26)

0.48 (.30)

0.52

Average lowest FiO₂^a

0.27 (.10)

0.23 (.9)

0.004

Average highest PEEP^a

5.2 (0.8)

5.4 (0.5)

0.41

Average lowest PEEP^a

5.0 (0.5)

5 (0)

0.37

Average highest PIP^a

20.6 (5)

14.3 (3)

0.005

Average lowest PIP^a

17.8 (4.7)

12 (0.6)

<0.001